Speaking about RAM I have a very strange problem which appears to be quite widespread those days. BIOS shows about 400MB less RAM available than the physical one reported.
Here are some details from the machine:
check-my-memory.py - version: SJ 2014-03-16
OK, you’re root
ANALYSIS:
Total of physical memory modules found 4096 MB in 1 memory module(s)
BIOS offers 3668 MB as usable
Memory seen by OS 3534 MB
BIOS version 08/02/2013
CPU is PAE enabled
CPU is x86_64 64-bit enabled
OS is x86_64 64-bit
SUMMARY:
Memory difference between DIMM hardware and BIOS offering 428 MB
Memory difference between BIOS offering and memory seen by OS 134 MB
Memory difference between DIMM hardware and memory seen by OS 562 MB
ADVICE:
Your BIOS is not offering all of your physical memory. Try to update your BIOS, and/or enable ‘memory hole remapping / hoisting’ in your BIOS to get more usable memory
Finally: show more detailed memory info from lshw and dmidecode. This can take up to 30 seconds …
description: System Memory
size: 4GiB
description: DIMM [empty]
description: SODIMM DDR3 Synchronous 1600 MHz (0,6 ns)
size: 4GiB
description: BIOS
size: 128KiB
capacity: 4032KiB
BIOS Information
Vendor: LENOVO
Version: H0ET94WW (2.54 )
Release Date: 08/02/2013
System Information
Manufacturer: LENOVO
Product Name: 33664NG
Version: ThinkPad Edge E530c
Maximum Capacity: 16 GB
Finished
[email protected]:~$ dmesg | grep BIOS
[ 0.000000] e820: BIOS-provided physical RAM map:
[ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009cfff] usable
[ 0.000000] BIOS-e820: [mem 0x000000000009d000-0x000000000009ffff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000000e0000-0x00000000000fffff] reserved
[ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x000000001fffffff] usable
[ 0.000000] BIOS-e820: [mem 0x0000000020000000-0x00000000201fffff] reserved
[ 0.000000] BIOS-e820: [mem 0x0000000020200000-0x0000000040003fff] usable
[ 0.000000] BIOS-e820: [mem 0x0000000040004000-0x0000000040004fff] reserved
[ 0.000000] BIOS-e820: [mem 0x0000000040005000-0x00000000873c6fff] usable
[ 0.000000] BIOS-e820: [mem 0x00000000873c7000-0x000000009ae9efff] reserved
[ 0.000000] BIOS-e820: [mem 0x000000009ae9f000-0x000000009af9efff] ACPI NVS
[ 0.000000] BIOS-e820: [mem 0x000000009af9f000-0x000000009affefff] ACPI data
[ 0.000000] BIOS-e820: [mem 0x000000009afff000-0x000000009f9fffff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000f8000000-0x00000000fbffffff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000fec00000-0x00000000fec00fff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000fed08000-0x00000000fed08fff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000fed10000-0x00000000fed19fff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000fed1c000-0x00000000fed1ffff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000fee00000-0x00000000fee00fff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000ff000000-0x00000000ff000fff] reserved
[ 0.000000] BIOS-e820: [mem 0x00000000ffc00000-0x00000000ffffffff] reserved
[ 0.000000] BIOS-e820: [mem 0x0000000100000000-0x000000015e5fffff] usable
[ 0.000000] SMBIOS 2.7 present.
[ 0.000000] DMI: LENOVO 33664NG/33664NG, BIOS H0ET94WW (2.54 ) 08/02/2013
[ 0.000000] Calgary: detecting Calgary via BIOS EBDA area
[ 0.100643] [Firmware Bug]: ACPI: BIOS _OSI(Linux) query ignored
[ 1.112549] BIOS EDD facility v0.16 2004-Jun-25, 0 devices found
[ 19.685894] thinkpad_acpi: ThinkPad BIOS H0ET94WW (2.54 ), EC unknown
[ 19.780993] hda_codec: CX20590: BIOS auto-probing.
[email protected]:~$ free -m
total used free shared buffers cached
Mem: 3534 2872 662 61 90 1367
-/+ buffers/cache: 1414 2120
Swap: 3864 0 3864
lspci
00:00.0 Host bridge: Intel Corporation 3rd Gen Core processor DRAM Controller (rev 09)
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor PCI Express Root Port (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09)
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)
00:16.0 Communication controller: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 (rev 04)
00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04)
00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller (rev 04)
00:1c.0 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 (rev c4)
00:1c.1 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 2 (rev c4)
00:1c.2 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 3 (rev c4)
00:1c.3 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 4 (rev c4)
00:1d.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)
00:1f.0 ISA bridge: Intel Corporation HM77 Express Chipset LPC Controller (rev 04)
00:1f.2 SATA controller: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)
00:1f.3 SMBus: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller (rev 04)
01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 635M] (rev a1)
02:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS5229 PCI Express Card Reader (rev 01)
03:00.0 Network controller: Broadcom Corporation BCM4313 802.11bgn Wireless Network Adapter (rev 01)
0c:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 07)
[email protected]:~$ lspci -v -s 00:02.0
00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09) (prog-if 00 [VGA controller])
Subsystem: Lenovo Device 5001
Flags: bus master, fast devsel, latency 0, IRQ 45
Memory at e1400000 (64-bit, non-prefetchable) [size=4M]
Memory at d0000000 (64-bit, prefetchable) [size=256M]
I/O ports at 6000 [size=64]
Expansion ROM at [disabled]
Capabilities:
Kernel driver in use: i915
After a bit of research my suggestion is BIOS issue related to part of the memory not getting remapped after reserving the necessary. They call it also the memory hole, but I don’t have any option in my BIOS to remap it.
There is a newer version of the BIOS but I can’t see any hot fix for this announced…
Anybody else ever stumbled upon such a scenario, any suggestions ?
P.S. I am booting with Legacy mode. Tried to boot UEFI today for the sake of testing but wouldn’t pass the welcome screen. Not sure if this could be related. As far as I know UEFI concerns only windows users.